CAJ | 학술논문

植被恢复及其对年均径流量影响的空间格局对黄土高原生态环境建设及水资源管理具有重要指导作用.在分析植被适宜性分布规律的基础上,基于黄河中游河口-龙门区间100 m地形高程模型(DEM)和专家经验进行了区域植被适宜性制图,并基于参数率定后的多年平均蒸散量计算公式和水平衡模型,估算了不同植树造林情景下年均径流量的变化.结果表明,河龙区间符合植被带分布规律的适宜区植树面积为6.6×10~3 km~2,次适宜区植树面积为4.8×10~3 km~2,分别占研究区总面积的5.8%和4.3%.土地覆被现状条件下区域产水约为33.8 mm(38.07×10~8 m~3).适宜区植树后,区域产水减少量约为1.9mm(2.12×10~2 m~3),减少5.6%.适宜区和次适宜区均植树后,区域产水减少量约为3.1 mm(3.49×10~8 m~3),减少9.2%.空间分布格局表明,区域局部减水最大达到48 mm.受气候条件影响.东南部高降雨量地区的流域适宜植树面积达45.1%,相应减水比例达36.0%.西北部低降雨量地区的流域植树面积约为0.7%,相应的减水比例为0.4%.
식피회복급기대년균경류량영향적공간격국대황토고원생태배경건설급수자원관리구유중요지도작용.재분석식피괄의성분포규률적기출상,기우황하중유하구-룡문구간100 m지형고정모형(DEM)화전가경험진행료구역식피괄의성제도,병기우삼수솔정후적다년평균증산량계산공식화수평형모형,고산료불동식수조림정경하년균경류량적변화.결과표명,하룡구간부합식피대분포규률적괄의구식수면적위6.6×10~3 km~2,차괄의구식수면적위4.8×10~3 km~2,분별점연구구총면적적5.8%화4.3%.토지복피현상조건하구역산수약위33.8 mm(38.07×10~8 m~3).괄의구식수후,구역산수감소량약위1.9mm(2.12×10~2 m~3),감소5.6%.괄의구화차괄의구균식수후,구역산수감소량약위3.1 mm(3.49×10~8 m~3),감소9.2%.공간분포격국표명,구역국부감수최대체도48 mm.수기후조건영향.동남부고강우량지구적류역괄의식수면적체45.1%,상응감수비례체36.0%.서북부저강우량지구적류역식수면적약위0.7%,상응적감수비례위0.4%.
Aims Vegetation is the fundamental measure to control erosion in the Loess Plateau. It is believed that forests use more water than grasslands and hence reduce average annual streamflow; however, the spatial distribution of vegetation restoration and its impacts on annual streamflow, especially on the regional scale, are poorly known. Our objectives were to map the vegetation suitability in the Hekou-Longmen (Short with He-Long) region of the middle reaches of Yellow River and assess the impact of afforestation on streamflow based on two plantation scenarios.Methods We assumed 1) the combined effects of bio-climatic zones on regional scale and local land-form determined vegetation suitability, 2) higher precipitation is more suitable for plantations and 3) the extent of soil moisture availability defmed by three local factors (slope, aspect and slope profile) depends on precipitation. We defined high, moderate and low vegetation suitability classes and developed a vegetation suitability map for the region using 100 m Digital Elevation Model (DEM) and the above assumptions. Plantation scenario 1 was developed using only the highly suitable area, and scenario 2 comprised both the highly and moderately suitable areas. The locally calibrated average annual water balance model of Zhang et al. (2001) was used to assess the impacts of afforestation on annual stream-flow in the study area.Important findings The highly suitable area for plantation covers 6.6×10~3 km~2, and the moderately suitable area covers 4.9×10~3 km~2, representing 5.8% and 4.3% of the total area, respectively. The plantation area made up 0-45% of individual catchments. The area suitable for plantation became increasingly patchy and sparse from south to north. Under current land cover status, average annual streamflow in the region was estimated to be 3.81×10~9 m~3 or 33.8 mm. Under scenario 1, average annual streamflow would be reduced by 2.12 ×10~9 m~3 or 1.9 mm (5.5%). Under scenario 2, the modeled streamflow reduction is 3.49×10~9 m~3 or 3.1 mm (9.2%). Corresponding to the spatial distribution of plantation, the reduction in streamflow is spatially variable. The rate of streamflow reduction varies from 0 to 36%. Minimum reduction occurred in the northwestern part of the region, where there is little area suitable for plantation development. Maximum reduction of 36% occurred in the southeastern part of the region where precipitation is highest.